There are a variety of applications in which two ingredients are kept separate from one another in a single container, such as a dual compartment container, so that at the appropriate time the two components can be used for their intended purpose. Prepackaging of specific doses or quantities is greatly facilitated by the use of multiple compartment containers and closures.
By the use of containers having precisely measure quantities of components, it is possible to develop packaging which is "user friendly" in the sense that mistakes made by the user are virtually avoided. For example, in pregnancy test kits which are used in the privacy of the home, it is necessary to precisely monitor a specific quantity of drops of two reagents into the urine specimen. Avoiding the necessity of counting drops eliminates a major source of mistake, and substantially increases the reliability of the test kit. Thus, if the precise quantities of both reagents are in a dual compartment container, and if access to that precisely monitored amount is extremely reliable, a greater degree of confidence in the test can be expected.
Another situation where precise monitoring and avoidance of mistakes is important is the mixing of small quantities of epoxy glue and other similar materials. Telephone lineman working on telephone wire high above the ground no longer splice wires. The present technology calls for a quick setting application of epoxy glue to bond the wires together. If it would be possible to avoid requiring the lineman to count drops of initiator to cause the epoxy to set, greater accuracy, greater strength and greater safety would be achieved.
In these situations and in others, considerable interest is now being shown in cap and container assemblies which cannot be opened by happenstance but which require a specific and positive step to be taken in order to have access to the contents. This is particularly true when the precise amount of the contents is important. It is also particularly significant when protection of either the user or the ingredients is of prime importance. In the case of reagents for medical purposes, a sterile environment is absolutely essential. In the case of other applications, such as the epoxy resin application described above, inadvertent contact by the ingredients on the skin is undesirable and should be avoided.
In actual practice, the assurance that the tube has not been opened prematurely is sometimes as important as the need to prevent undesirable tampering, so as to be assured of the integrity of the material. This is true because the contents, while valuable, are not dangerous. It is very important to know whether or not the contents have been contaminated or, perhaps, partially spilled. Particularly when single unit doses are provided in compartments of a container, it is important to know that the full quantity of medicine which has been prescribed has also been delivered to the patient.
Prior art devices have not yet produced a practical multiple compartment container and closure assembly which is capable of being transported safely without concern for inadvertent opening of the containers while at the same time provides for a quick and uncomplicated opening of the two components at the same time. One such design which has been relatively unsuccessful includes the one piece molding of a container and closure so that the cap can be torn from the container, by twisting or pulling. This has been unacceptable as a method because the separation of the container from the closure is done in a way that pressure is applied to the container. This positive pressure often times results in spurts of contents escaping from container during the opening process, rather than when the contents are to be used. These prior art designs also are incapable of re-closing the container once the closure has been separated from the containers. To remedy this, plug type members have been proposed for use with the other end of the closure, so that it can be inverted and forced down on the end of the tube after it has been opened. This, of course, exposes the torn off ends of the cap and any portion of the contents which may have spattered onto the torn ends. Additionally, it employs a portion of the cap which has been exposed to the environment as the secondary closure mechanism.
Container and closure assemblies which are designed for single compartment containers can be fabricated in round containers, so that the end can be threaded and selectively removed and attached. An example of this type of closure, with a built in piercing device, is shown in U.S. Pat. Nos. 4,340,147 and 3,454,196. Neither design is suitable for use with a plurality of compartments, unless each of the compartments is to be opened with its own cap assemble. U.S. Pat. Nos. 4,146,152 and 1,695,190 describe closures for single compartment containers which are even less suitable for adaptation to multiple compartment container and closure assemblies.
Accordingly, it is quite important that a new and improved container and closure assembly be developed which would have a reliability of use and would protect both the contents and the user from unwanted contamination. It would be of particular value if the device could be provided which would permit continued use of the container once access to the contents has been made.